Connecting device, method for manufacturing a connecting device, screw sleeve

Abstract

Connection device (1A, 1B) for fluidic connection of a suction hose (2) with a functional unit (3A, 3B), in particular a suction device (4), a tool (5) and / or a nozzle, wherein the connection device (1A, 1B) has a first, in particular hollow cylindrical, connection section (6) and a second, in particular hollow cylindrical, connection section (7), wherein one of the connection sections (6) is connectable to the suction hose (2) and the other connection section (7) is connectable to the functional unit (3A, 3B), wherein one of the connection sections (6) is located at least partially within the other connection section (7) and bears with its outer circumference (15) against the inner circumference (14) of the other connection section (7), wherein the two connection sections (6, 7) are rotatably mounted relative to each other in order to provide rotation compensation for the suction hose (2),and wherein an electrical connection exists between the two connecting sections (6, 7) to provide an antistatic function, wherein the first connecting section (6) is a screw sleeve, characterized in that the first connecting section (6) comprises a radially deformable spring section (8) with which contact is made with the second connecting section (7).

Description

[0001] The invention relates to a connecting device for the fluidic connection of a suction hose to a functional unit, in particular a suction device, a tool and / or a nozzle, wherein the connecting device has a first hollow cylindrical connecting section and a second hollow cylindrical connecting section, wherein one of the connecting sections can be connected to the suction hose and the other connecting section can be connected to the functional unit, wherein one of the connecting sections is located at least partially within the other connecting section and rests with its outer circumference against the inner circumference of the other connecting section, wherein the two connecting sections are mounted rotatably relative to one another in order to provide rotation compensation for the suction hose, and wherein an electrical connection exists between the two connecting sections to provide an antistatic function.The first connecting section is a screw sleeve.

[0002] The first hollow cylindrical connecting section is, for example, a screw sleeve and the second connecting section is, for example, a sleeve. The first connecting section is expediently screwed onto the suction hose and inserted into the second connecting section. The second connecting section is, for example, fastened to a suction device. The outer circumference of the first connecting section rests against the inner circumference of the second connecting section. This provides, in particular, electrical contact between the first connecting section and the second connecting section, which serves to provide the antistatic function. An electrical connection to an earthing conductor is thus provided via the suction hose and the connecting device, so that static charging can be prevented.

[0003] The first connecting section and the second connecting section are mounted so that they can rotate relative to each other. In particular, the first connecting section can rotate freely relative to the second connecting section. The rotatable mounting of the first connecting section relative to the second connecting section serves to provide rotational compensation for the suction hose. The rotational compensation prevents twisting of the suction hose during operation, which could lead to an undesired path of the suction hose and / or stiffening of the suction hose.

[0004] For rotational compensation, it is necessary that the first connecting section can be rotated relative to the second connecting section without excessive force. In particular, the torque required to rotate the first connecting section must be smaller than the torsional moment of the twisted suction hose. The torque required to rotate the first connecting section depends on the friction between the first connecting section and the second connecting section.

[0005] To minimize friction, the outer diameter of the first connecting section can be designed to be correspondingly small relative to the inner diameter of the second connecting section. However, in this case, there is a risk that the two connecting sections will no longer touch each other sufficiently, thus compromising the electrical contact between the two connecting sections, thus rendering the antistatic function ineffective.

[0006] DE 10 2014 119 243 A1 describes a connector for a suction hose. The connector comprises a tubular body with a peripheral wall defining a receptacle. A holder for the suction hose is inserted into the receptacle. The holder comprises a tubular holding body and is rotatably inserted into the receptacle.

[0007] US 5,797,162 A describes a connecting assembly for attachment to a tubular portion of a rod assembly. The connecting assembly comprises a clip, a hose connector, and a housing. The clip comprises a plurality of spaced fingers separated by slots.

[0008] DE 10 2017 115 653 A1 describes a suction hose with a hose section comprising a flexible dust removal hose body and a flexible sheathed hose body. A retaining element is attached to an outer surface of the sheathed hose body. The retaining element is designed, in particular, as a tape body, for example, as an adhesive tape.

[0009] An object of the invention is to modify the connecting device mentioned at the outset in such a way that both the rotation compensation and the antistatic function can be reliably provided.

[0010] The object is achieved by a connecting device according to claim 1.

[0011] The first connecting section of the connecting device comprises a spring section that is deformable in the radial direction. This spring section is used to engage the first connecting section with the second connecting section.

[0012] The spring section forms the outer circumference with which the first connecting section rests against the inner circumference of the second connecting section. The spring section is deformable in the radial direction, in particular elastically deformable. Due to its deformability, the spring section can yield relative to the inner circumference of the second connecting section. As a result, the first connecting section remains sufficiently easy to rotate relative to the second connecting section, even with a larger outer diameter. The outer diameter of the first connecting section can be designed larger than before (while the inner diameter of the second connecting section remains the same), which ensures that the two connecting sections are constantly in contact and thus the antistatic function is always maintained.

[0013] Advantageous further training courses are explained below.

[0014] The second connecting section is preferably a sleeve.

[0015] The spring section preferably has one or more slots. The one or more slots preferably extend in the axial direction of the first connecting section. The one or more slots extend in particular to a first end face of the first connecting section. The multiple slots are expediently arranged distributed around the circumference of the first connecting section. The deformability of the spring section can be ensured in a simple manner by means of the slots.

[0016] Preferably, the spring portion is an axial portion of the first connecting portion. In a non-deformed state, the spring portion expediently defines the maximum outer circumference of the first connecting portion. In a state in which the outer circumference abuts the inner circumference, the spring portion is expediently elastically deformed.

[0017] Furthermore, an arrangement is provided, comprising a suction hose, a functional unit and a connecting device as described above, wherein one of the connecting sections is connected to the suction hose and the other connecting section is connected to the functional unit and the connecting device provides an electrical and a fluidic connection between the suction hose and the functional unit.

[0018] Furthermore, a method for producing a connecting device according to one of the preceding claims is provided, comprising the steps of: producing the first connecting section with a first manufacturing tolerance, according to which the outer diameter of the first connecting section is in a first tolerance range, producing the second connecting section with a second manufacturing tolerance, according to which the inner diameter of the second connecting section is in a second tolerance range, wherein the difference between the upper limit value of the first tolerance range is greater than the lower limit value of the second tolerance range.

[0019] Preferably, the upper limit value of the first tolerance range is at least 0.1 mm, in particular at least 0.15 mm or at least 0.2 mm, greater than the lower limit value of the second tolerance range.

[0020] Preferably, the lower limit value of the first tolerance range is a maximum of 0.4 mm, in particular a maximum of 0.3 mm, smaller than the upper limit value of the second tolerance range.

[0021] Furthermore, a screw sleeve made of electrically conductive plastic is provided, comprising a hollow cylindrical base section which has an internal thread with which the screw sleeve can be screwed onto a suction hose, wherein a hollow cylindrical spring section adjoins the base section in the axial direction, which spring section has a plurality of slots running in the axial direction, is elastically deformable radially inwardly and, in a non-deformed state, defines the maximum outer circumference of the screw sleeve.

[0022] The screw sleeve can be used in particular as the above-mentioned first connecting portion.

[0023] The spring section, in particular the first connecting section, for example the screw sleeve, is made, for example, of polypropylene, in particular of a thermoplastic material. The spring section, in particular the first connecting section, for example the screw sleeve, expediently contains soot particles, which ensure electrical conductivity.

[0024] The term “electrically conductive plastic” therefore also refers in particular to a plastic, for example polypropylene, with added electrically conductive particles, for example electrically conductive soot particles.

[0025] With reference to the figures, exemplary embodiments are explained below. Fig. 1 an arrangement comprising a suction device, a suction hose, a functional unit and two connecting devices, Fig.2 a perspective view of a screw sleeve, Fig. 3 another perspective view of a screw sleeve, Fig. 4 a connecting device, Fig. 5 a section through the connecting device along the section line AA of the Fig. 4, Fig. 6 Tolerance ranges in the manufacture of a connecting device, and Fig. 7 a flowchart of a method for producing a connecting device.

[0026] The Fig. 1 shows an arrangement 10 comprising a first functional unit 3A, a second functional unit 3B, a suction hose 2, a first connecting device 1A, and a second connecting device 1B. The arrangement 10 represents an exemplary application context for the connecting devices 1A and 1B. The connecting devices 1A and 1B can also each be provided separately.

[0027] The first connecting device 1A serves to electrically and fluidically connect the first functional unit 3A to the suction hose 2. The second connecting device 1B serves to electrically and fluidically connect the second functional unit 3B to the suction hose 2.

[0028] It should be noted that the arrangement 10 can alternatively also comprise only one of the connecting devices 1A, 1B. The connection of the suction hose 2 to the respective other functional unit 3A or 3B can then be made in another way, for example, by a conventional functional device or by direct connection. For example, the second functional unit 3B can be connected directly to the suction hose 2.

[0029] The first functional unit 3A is a suction device 4. By way of example, the suction device 4 is designed as a mobile vacuum cleaner having a plurality of wheels 18 with which the mobile vacuum cleaner is supported against the ground and can be moved relative to the ground. The suction device 4 comprises a vacuum unit 33 with which a vacuum can be provided at a connection 34 of the suction device 4. The vacuum unit 33 is, for example, a blower. The suction device 4 further comprises a grounding conductor (not shown) which is electrically connected to the suction hose 2 via the first connecting device 1a.

[0030] The suction hose 2 provides a fluidic connection between the suction device 4, in particular the connection 34, and the second functional unit 3B. The suction hose 2 is connected to the suction device 4, in particular the connection 34, via the first connecting device 1A. Suctioned air and / or particles are conveyed into the suction device 4 via the suction hose 2 and the first connecting device 1A.

[0031] The suction hose 2 is expediently electrically conductive so that an electrical connection can be provided between the suction device 4 and the second functional unit 3B by means of the suction hose 2. This electrical connection runs from the second functional unit 3B via the (optionally provided) second connecting device 1B, the suction hose 2 and the first connecting device 1A to the suction device 4. The electrical connection ends in particular at the grounding conductor of the suction device. The ohmic resistance of the electrical connection is expediently less than 10 megaohms. The electrical connection provides an antistatic function; i.e., static charges on the suction hose 2 and / or the second functional unit 3B are discharged via the electrical connection to the grounding conductor of the suction device 4.

[0032] The suction hose 2 is made of flexible material in particular so that the suction hose 2 can be flexibly adjusted in its course.

[0033] The second functional unit 3B comprises, for example, a tool 5 and / or a nozzle. The second functional unit 3B is, in particular, a work tool. The tool 5 can be, for example, a power tool, expediently a saw, grinder, or drill. The second functional unit 3B is connected to the suction hose 2 via the second connecting device 1B. Dust generated and / or present in the area of ​​the functional unit 3B can be vacuumed directly at the functional unit 3B and transported via the suction hose 2 to the suction device 4. The dust is expediently transported from the functional unit 3B via the second connecting device 1B (if present), the suction hose 2, and the first connecting device 1A to the suction device 4.

[0034] The following will discuss the two connecting devices 1A and 1B in more detail. The two connecting devices 1A and 1B can be identical or different. The features explained below are expediently present in both connecting devices 1A, 1B. The following will primarily focus on the first connecting device 1A. The following explanations also apply analogously to the second connecting device 1B and, in particular, its relationship to the second functional unit 3B.

[0035] The connecting device 1A has a first connecting section 6 and a second connecting section 7. The two connecting sections 6, 7 are expediently made of electrically conductive material, in particular electrically conductive plastic. The electrical resistance of the connecting sections 6, 7 is expediently less than 10 megohms.

[0036] First, to the first connection section 6: The first connecting section 6 is connected to the suction hose 2, in particular, it is fastened thereto. The first connecting section 6 is, for example, a screw sleeve 9 and is expediently screwed onto the suction hose 2. The first connecting section 6 is designed as a hollow cylinder. The outer cylindrical surface of the connecting section 6 forms the outer circumference 15. Expediently, there is no thread on the outer circumference 15. The first connecting section 6 comprises a free, cylindrical interior space, which functions as a conduit section for the fluidic connection between the suction hose 2 and the functional unit 3A.

[0037] The first connecting section 6 is divided in the axial direction into two axial sections—a spring section 8 and a base section 21. The spring section 8 is located on the side facing away from the suction hose 2, and the base section 21 is located on the side facing the suction hose 2. The spring section 8 is deformable in the radial direction, in particular more easily deformable in the radial direction than the base section 21. Advantageously, the spring section 8 is elastically deformable in the radial direction. The spring section 8, for example, occupies at least 1 / 6 and at most 1 / 4 of the axial extent of the first connecting section 6.

[0038] The outer diameter of the first connecting section 6 is expediently larger than the axial extent of the first connecting section 6.

[0039] The base section 21, for example, has a smaller outer diameter than the spring section 8. Starting from the base section 21, the outer diameter of the spring section 8 increases in the axial direction away from the base section 21. In the axial region with the maximum outer diameter, the spring section 8 bears against the inner circumference 14 of the second connecting section 7. The spring section 8 forms the outer circumference 15 of the first connecting section 6, which bears against the inner circumference 14 of the second connecting section 7. The spring section 8 is expediently deformed inward in the radial direction by the inner circumference 14, in particular elastically deformed.

[0040] Now to the second connecting section 7: The second connecting section 7 is connected to the functional unit 3A, in particular, is fastened thereto. The second connecting section 7 is, for example, a sleeve 11 or a section of a sleeve. The second connecting section 7 is designed as a hollow cylinder. The inner cylindrical surface of the second connecting section 7 forms the inner circumference 14. The second connecting section 7 comprises a cylindrical interior. Expediently, no thread is present on the inner circumference 14 of the second connecting section 7.

[0041] The following will discuss the interaction of the two connecting sections 6 and 7: The first connecting section 6 is located within the second connecting section 7. By way of example, the first connecting section 6 is fully inserted into the hollow-cylindrical second connecting section 7, in particular into its cylindrical interior. The first connecting section 6 rests with its outer circumference 15 against the inner circumference 14 of the second connecting section 7. In particular, the first connecting section 6 rests with the spring section 8 against the inner circumference 14.

[0042] By the spring section 8 being in contact with the inner circumference 14, an electrical contact is established between the two connecting sections 6, 7. An electrical connection of, in particular, less than 10 megohms exists between the two connecting sections 6, 7, which provides the antistatic function mentioned above.

[0043] The two connecting sections 6, 7 are mounted rotatably relative to each other to provide rotational compensation for the suction hose 2. The first connecting section 6 is rotatable, in particular freely rotatable, about its longitudinal axis relative to the second connecting section 7.

[0044] On the end face of the second connecting section 7 facing away from the first functional unit 3A, a fastening ring 19 is arranged, which prevents the first connecting section 6 from being pulled out of the second connecting section 7. The inner diameter of the fastening ring 19 is smaller than the outer diameter of the first connecting section 6. The fastening ring 19 has an annular opening through which the suction hose 2 extends into the second connecting section 7.

[0045] The following is based on the Fig. 2 and Fig.3 discusses a possible design of the first connecting section 6. The first connecting section 6 is embodied here as a screw sleeve 9, for example. The screw sleeve 9 can also be provided separately.

[0046] The first connecting section 6 is expediently designed as already explained above. The first connecting section 6 comprises the spring section 8, which here is also an axial section, in particular an axial end section, of the first connecting section 6. The spring section 8 extends to the first end face 25 of the first connecting section 6. The spring section 8 is hollow-cylindrical, in particular annular. Expediently, no internal thread and / or external thread is provided on the spring section 8.

[0047] For example, the spring section 8 has an annular bead 12, via which the spring section 8 is pressed against the inner circumference 14. The annular bead 12 is located in the area of ​​the first end face 25. The annular bead 12 forms the outer circumference 15.

[0048] The spring section 8 has a plurality of slots 16. The slots 16 extend in the axial direction of the first connecting section 6, in particular parallel to the axial direction. The slots 16 extend in particular to the first end face 25 of the first connecting section 6. The slots 16 open in particular at the first end face 25. The slots 12 extend through the annular bead 12.

[0049] The plurality of slots 16 are expediently arranged distributed around the circumference of the first connecting section 6. The slots 16 are arranged, in particular, at equal angular distances from one another. Preferably, at least 6, 7, 8, 9, or 10 slots 16 are present. Exactly, exactly 6, 7, 8, 9, or 10 slots 16 are present.

[0050] The slots 16 are expediently present only in the spring section 8 and end there. In particular, the slots 16 do not extend into the base section 21. The slots 16 expediently extend over at least 1 / 7 or at least 1 / 6 of the axial extent of the first connecting section 6 and preferably over at most 1 / 5 of the axial extent of the first connecting section 6.

[0051] By way of example, the slots 16 are each between 4 mm and 6 mm, in particular between 4.5 mm and 5.5 mm, preferably 4.9 mm long. The slots are preferably between 0.3 mm and 0.7 mm, preferably 0.5 mm wide.

[0052] Between each two adjacent slots 16 there is a circumferential section 17. The outer extension of the circumferential sections 17 in the circumferential direction - i.e. the circular arc between two adjacent slots 16 - is expediently 15 mm to 20 mm.

[0053] The base section 21 has an internal thread 22 with which the first connecting section 6 is screwed or can be screwed onto the suction hose 2. The internal thread 22 expediently extends to the second end face 26 of the first connecting section 6.

[0054] The base section 21 and the spring section 8 together form an outer cylindrical section. An inner cylindrical section 24 lies within this outer cylindrical section. The inner cylindrical section 24 extends in the axial direction from the first end face 25 to the central axial region of the connecting section 6. The inner cylindrical section 24 overlaps in the axial direction with the internal thread 22. The inner cylindrical section 24 is connected to the base section 21 via an annular connecting section. The inner cylindrical section 24 has a plurality of ribs 23 which run in the axial direction starting from the first end face 25 and are arranged on the outside of the inner cylindrical section 24. The ribs 23 are arranged distributed around the circumference of the inner cylindrical section 24. The ribs 23 are expediently spaced radially from the spring section 8.The ribs 23 preferably occupy the same axial area as the spring section 8.

[0055] The length—i.e., the axial extent—of the first connecting section 9 is expediently between 20 mm and 40 mm, in particular between 27 mm and 33 mm. The outer diameter of the first connecting section 9 is expediently between 35 mm and 55 mm.

[0056] The following is based on the Fig. 4 and Fig. 5 discusses a possible embodiment of the first connecting device 1A. The first connecting device 1A is expediently designed as explained above. The second connecting device 1B is expediently designed correspondingly.

[0057] The fastening ring 19 is located on the end face of the connecting device 1A facing the suction hose 2. The fastening ring 19 rests against the end face and the inner circumference of the second connecting section 7. The fastening ring 19 is detachably attached to the second connecting section 7, for example via a snap-in connection 28.

[0058] The second connecting section 7 comprises, by way of example, an outer cylindrical section 31 and an inner cylindrical section 32. The inner cylindrical section 32 adjoins the first connecting section 6 in the axial direction. The first connecting section 6 is arranged in the axial direction between the fastening ring 19 and the inner cylindrical section 32, so that the first connecting section 6 is limited on both sides in its movement relative to the second connecting section 7 in the axial direction.

[0059] The first connecting section 6 and the second connecting section 7 together provide a fluidic line 29 via which air and / or particles can be transported between the suction hose 2 and the functional unit 3A.

[0060] As in the Fig. 5, the first connecting section 7 rests with the outer circumference 15 of the spring section 8, in particular the outer circumference of the annular bead 12, on the inner circumference 14.

[0061] In the Fig. 4 and Fig. 5, the connecting section 6 is screwed onto the suction hose 2. The suction hose 2 has an external thread 27, onto which the first connecting section 6 is screwed. Conveniently, a corresponding external thread is present at both ends of the suction hose 2. Conveniently, a connecting section 6 is screwed onto both ends of the suction hose.

[0062] In the following, with reference to the Fig. 6 and Fig. 7 will go into more detail about the manufacture of the connecting device 1A.

[0063] The connecting device 1A is expediently manufactured by injection molding. Preferably, the first connecting section 6 and the second connecting section 7 are each manufactured as individual components, in particular as individual injection-molded components.

[0064] During manufacture, the connecting sections 6 and 7 are subject to respective manufacturing tolerances, which particularly affect the outer diameter of the first connecting section 6 and the inner diameter of the second connecting section 7. Due to the manufacturing tolerances, a first tolerance range T1 results for the outer diameter of the first connecting section 6 and a second tolerance range T2 for the inner diameter of the second connecting section 7. If a plurality of first connecting sections 6 and second connecting sections 7 are manufactured, the outer diameters and inner diameters of the manufactured connecting sections 6, 7 will be distributed within the tolerance ranges T1, T2 due to the manufacturing tolerances of the manufacturing process.

[0065] The two tolerance ranges T1, T2 can each be defined via an expected value E1, E2, an upper limit value OG1, OG2 and a lower limit value UG1, UG2.

[0066] When manufacturing a plurality of connecting sections 6, 7, due to these manufacturing tolerances, there will also be connecting sections 6, 7 whose outer diameter or inner diameter lies on one of the limit values ​​OG1, OG2, UG1, UG2.

[0067] During the manufacture of a connecting device 1A, a first connecting section 6 is combined with a second connecting section 7. It is important to ensure that each manufactured connecting device 1A provides both the aforementioned rotational compensation and the aforementioned antistatic function. This can be ensured, in particular, by selecting the tolerance ranges T1, T2 as explained below.

[0068] In particular, the tolerance ranges T1, T2 are selected such that the upper limit value OG1 of the first tolerance range T1 is greater than the lower limit value UG2 of the second tolerance range T2.

[0069] This means that it is explicitly permitted that in the most unfavorable case for rotational compensation—namely, the combination of the limit values ​​OG1 and UG2—the outer diameter of the first connecting section 6 may be larger than the inner diameter of the second connecting section 7. This results in a kind of "overlap" between the outer diameter and the inner diameter. Due to the elastically deformable spring section 8, it can also be ensured in this case that a rotational movement of the first connecting section 6 relative to the second connecting section 7 is smooth enough to provide rotational compensation.

[0070] By way of example, the upper limit value OG1 of the first tolerance range T1 is at least 0.1 mm, in particular at least 0.15 mm, greater than the lower limit value UG of the second tolerance range T2.

[0071] By selecting a larger upper limit value OG1 for the outer diameter, the first tolerance range T1 can be shifted further to the right (compared to the state of the art)—that is, toward larger outer diameters. This allows the maximum distance between the lower limit value UG1 of the outer diameter and the upper limit value OG2 of the inner diameter to be reduced, so that even in the unfavorable case for the antistatic function—namely, the combination of the limit values ​​UG1 and OG2—electrical contact between the two connecting sections 6, 7 is maintained, thus providing the antistatic function.

[0072] For example, the lower limit value UG1 of the first tolerance range T1 is a maximum of 0.4 mm, in particular a maximum of 0.3 mm, smaller than the upper limit value UG2 of the second tolerance range T2.

[0073] The first tolerance range T1 is preferably smaller than or equal to the second tolerance range T2. The first tolerance range T1—i.e., the difference between OG1 and UG1—is preferably 0.2 mm. The second tolerance range T2—i.e., the difference between OG2 and UG2—is preferably 0.2 mm or 0.3 mm.

[0074] The following table lists exemplary values ​​for the two tolerance ranges T1, T2, specifically for three different types of the first connecting section 6 and the second connecting section 7. To produce a connecting device, a first connecting section 6 and a second connecting section 7 of the same type are combined. Outer diameter inner diameter first connection second connecting section 6 (mm) section 7 (mm) Type 1 40,05 ± 0,1 40,09 ± 0,1 Type 2 46,05 ± 0,1 46,13 ± 0,15 Type 3 51,65 ± 0,1 51,65 ± 0,15

[0075] The Fig.7 shows a flow chart of a method for producing a connecting device 1A explained above. The method comprises the steps: producing S1 the first connecting section 6 with a first manufacturing tolerance, according to which the outer diameter of the first connecting section 6 is in a first tolerance range T1, producing S2 the second connecting section 7 with a second manufacturing tolerance, according to which the inner diameter of the second connecting section 7 is in a second tolerance range T2, wherein the upper limit value OG1 of the first tolerance range T1 is greater than the lower limit value UG2 of the second tolerance range T2.

[0076] The method expediently comprises the further step of inserting the first connecting section 6 into the second connecting section 7.

[0077] By means of the manufacturing method, a plurality of first connecting sections 6 and second connecting sections 7 are expediently produced. These include at least one first connecting section 6 with an upper limit value OG1, one first connecting section 6 with a lower limit value UG1, one second connecting section 7 with an upper limit value OG2, and one second connecting section 7 with a lower limit value UG2. The limit values ​​OG1, OG2, UG1, UG2 expediently have one or more of the relationships explained above.

[0078] The majority of connecting sections 6, 7 are used to produce connecting devices.

[0079] Further exemplary details will be explained below.

[0080] The suction hose 2 is preferably provided with a textile covering. The textile covering is preferably electrically conductive.

[0081] The screw sleeve 9 is mounted in the sleeve 11 for unlimited rotation. The screw sleeve 9 and the sleeve 11 are made of conductive plastic. The antistatic conductivity from the screw sleeve 9 to the sleeve 11 is provided by the annular bead 12, which rubs against the inner diameter of the sleeve 11.

[0082] The screw sleeve 9 and the sleeve 11 are preferably manufactured by injection molding. The manufacturing process for the screw sleeve 9 and the sleeve 11 has a maximum tolerance of + / - 0.1 mm for the inner diameter of the sleeve 11 and the outer diameter of the screw sleeve 9.

[0083] In conventional connecting devices, the two most unfavorable tolerance pairings may result in an air gap between the sleeve 11 and the screw sleeve 9 (which impairs the electrical conductivity) or in a compression of the two parts, which may lead to a loss of rotational compensation.

[0084] The present screw sleeve 9 is slotted in the area of ​​the annular bead 12 so that spring segments are formed which reduce the effect of jamming.

[0085] During manufacturing, the tolerances of the sleeve 11 and the screw sleeve 9 are designed so that even in the most unfavorable pairing case, contact between the sleeve 11 and the screw sleeve 9 is ensured, thus ensuring antistatic conductivity. The spring effect of the spring section prevents jamming of the screw sleeve 9 in the extreme case where the outer diameter of the screw sleeve 9 is at its maximum and the inner diameter of the sleeve 11 at its minimum.

[0086] The dimensions of the screw sleeve and the socket are designed so that: - the largest outer diameter of the screw sleeve and the smallest inner diameter of the socket result in a maximum overlap of 0.2 mm; - due to the tolerances at the smallest outer diameter of the screw sleeve and the largest inner diameter of the sleeve, there is a clearance of 0.3 mm between the screw sleeve and the sleeve.

Claims

[1] Connecting device (1A, 1B) for the fluidic connection of a suction hose (2) to a functional unit (3A, 3B), in particular a suction device (4), a tool (5) and / or a nozzle, wherein the connecting device (1A, 1B) has a first, in particular hollow-cylindrical, connecting section (6) and a second, in particular hollow-cylindrical, connecting section (7), wherein one of the connecting sections (6) is connectable to the suction hose (2) and the other connecting section (7) is connectable to the functional unit (3A, 3B), wherein one of the connecting sections (6) is located at least partially within the other connecting section (7) and rests with its outer circumference (15) against the inner circumference (14) of the other connecting section (7), wherein the two connecting sections (6, 7) are mounted rotatably relative to one another in order to provide rotational compensation for the suction hose (2),and wherein there is an electrical connection between the two connecting sections (6, 7) to provide an antistatic function, wherein the first connecting section (6) is a screw sleeve, , characterized by that the first connecting section (6) comprises a spring section (8) which is deformable in the radial direction and with which the contact with the second connecting section (7) takes place. [2] Connecting device (1A, 1B) according to claim 1, characterized by that the spring portion (8) has one or more slots (16). [3] Connecting device (1A, 1B) according to claim 2, characterized by that the one or more slots (16) extend in the axial direction of the first connecting section (6). [4] Connecting device (1A, 1B) according to claim 2 or 3, characterized by that the one or more slots (16) extend to a first end face (25) of the first connecting section (6). [5] Connecting device (1A, 1B) according to one of claims 2 to 4, characterized by that the plurality of slots (16) are arranged distributed around the circumference of the first connecting section (6). [6] Connecting device (1A, 1B) according to one of the preceding claims, characterized by that the spring section (8) is an axial section of the first connecting section (6). [7] Connecting device (1) according to one of the preceding claims, characterized by that the spring portion (8) in a non-deformed state defines the maximum outer circumference of the first connecting portion (6). [8] Connecting device (1) according to one of the preceding claims, characterized by that the second connecting section (7) is a sleeve (11) or a section of a sleeve. [9] Arrangement (10) comprising a suction hose (2), a functional unit (3A, 3B) and a connecting device (1A, 1B) according to one of the preceding claims, wherein one of the connecting sections (6) is connected to the suction hose (2) and the other connecting section (7) is connected to the functional unit (3A, 3B) and the connecting device (1A, 1B) provides an electrical and a fluidic connection between the suction hose (2) and the functional unit (3A, 3B). [10] Method for producing a connecting device (1) according to one of the preceding claims, comprising the steps: Producing (S1) the first connecting section (6) with a first manufacturing tolerance, according to which the outer diameter of the first connecting section (6) is in a first tolerance range (T1), Producing (S2) the second connecting portion (7) with a second manufacturing tolerance, according to which the inner diameter of the second connecting portion (7) is in a second tolerance range (T2), wherein the upper limit value (OG1) of the first tolerance range (T1) is greater than the lower limit value (UG2) of the second tolerance range (T2). [11] Method according to claim 10, wherein the upper limit value (OG1) of the first tolerance range (T1) is at least 0.1 mm, in particular at least 0.15 mm or at least 0.2 mm greater than the lower limit value (UG2) of the second tolerance range (T2). [12] Method according to claim 10 or 11, wherein the lower limit value (UG1) of the first tolerance range (T1) is smaller by a maximum of 0.4 mm, in particular a maximum of 0.3 mm, than the upper limit value (OG2) of the second tolerance range (T2). [13] Screw sleeve (9) made of electrically conductive plastic, comprising a hollow cylindrical base section (21) which has a thread, in particular an internal thread (22), with which the screw sleeve (9) can be screwed onto a suction hose (2), characterized by a hollow cylindrical spring section (8) which adjoins the base section (21) in the axial direction and has a plurality of slots (16) running in the axial direction, is elastically deformable inwardly in the radial direction and, in a non-deformed state, defines the maximum outer circumference of the screw sleeve (9).

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